U.S. patent application number 14/526995 was filed with the patent office on 2015-04-30 for device for driving a plurality of light blocks of a motor vehicle.
The applicant listed for this patent is VALEO VISION. Invention is credited to Christophe Roger.
Application Number | 20150115795 14/526995 |
Document ID | / |
Family ID | 49949883 |
Filed Date | 2015-04-30 |
United States Patent
Application |
20150115795 |
Kind Code |
A1 |
Roger; Christophe |
April 30, 2015 |
DEVICE FOR DRIVING A PLURALITY OF LIGHT BLOCKS OF A MOTOR
VEHICLE
Abstract
A driver device (P) for a plurality of light blocks (LED_DRL/PL,
LED_TI) of a motor vehicle comprising at least two inputs (P1, P2),
each of the inputs being suitable for receiving, respectively, a
first and a second execution control signals (SCF_DRL, SCF_TI/PL),
the driver device being suitable for selecting at least one of the
light blocks as a function of at least one of the execution control
signals and delivering an electrical power supply to said selected
light block, the driver device comprises at least one controller
receiving said execution control signals, the controller being
suitable for delivering, as a function of the logic state of
execution control signals, a switching control signal (SCC) for
switching the electrical power supply to the selected light block
or blocks and a control signal for controlling the level of power
(SCA) of the electrical power supply of the selected light block or
blocks.
Inventors: |
Roger; Christophe;
(Saint-Lambert-La-Potherie, FR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
VALEO VISION |
Bobigny Cedex |
|
FR |
|
|
Family ID: |
49949883 |
Appl. No.: |
14/526995 |
Filed: |
October 29, 2014 |
Current U.S.
Class: |
315/77 |
Current CPC
Class: |
B60Q 1/34 20130101; B60Q
1/28 20130101; B60Q 1/0076 20130101; B60Q 1/0088 20130101; H05B
45/00 20200101; B60Q 1/04 20130101; B60Q 1/1407 20130101; H05B
45/10 20200101 |
Class at
Publication: |
315/77 |
International
Class: |
B60Q 1/00 20060101
B60Q001/00; B60Q 1/28 20060101 B60Q001/28; B60Q 1/34 20060101
B60Q001/34; B60Q 1/04 20060101 B60Q001/04 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 30, 2013 |
FR |
1360592 |
Claims
1. A driver device (P) for a plurality of light blocks (LED_DRL/PL,
LED_TI) of a motor vehicle, said driver device comprising at least
two inputs (P1, P2) each of said at least two inputs being suitable
for receiving, respectively, a first and a second execution control
signals (SCF_DRL, SCF_TI/PL), said driver device being suitable for
selecting at least one of said plurality of light blocks as a
function of at least one of said first or said second execution
control signals and delivering an electrical power supply to said
selected light block, said driver device comprises at least one
controller receiving said execution control signals, said at least
one controller being suitable for delivering, as a function of a
logic state of said first and second execution control signals, a
switching control signal (SCC) for switching said electrical power
supply to said selected light block or blocks and a control signal
for controlling a level of power (SCA) of said electrical power
supply of said selected light block or blocks.
2. The driver device (P) according to claim 1, wherein said driver
device is suitable for selecting a light function to be executed as
a function of a combination of the logic states of said first and
second execution control signals (SCF_DRL, SCF_TI/PL) received on
said at least two inputs (P1, P2) of said driver device and for
selecting at least one of said plurality of light blocks
(LED_DRL/PL, LED_TI) for the execution of said selected light
function.
3. The driver device (P) according to claim 1, wherein said driver
device is suitable for selecting a light function out of a
predetermined number of selectable light functions, the number of
said at least two inputs (P1, P2) for said first and second
execution control signals (SCF_DRL, SCF_TI/PL) from said driver
device being less than said predetermined number of selectable
light functions.
4. The driver device (P) according to claim 2, wherein said driver
device is suitable for selecting a light function to be executed as
a function of an activation table (AT) receiving as input a logic
state of each of said first and second execution control signals
(SCF_DRL, SCF_TI/PL) and delivering said light function to be
selected.
5. The driver device (P) according to claim 4, wherein said
activation table (AT) is implemented by a look-up table (AT) in
said at least one controller or by a microprogram driven by said at
least one controller.
6. The driver device (P) according to claim 2, wherein said at
least one controller is suitable for delivering a switching control
signal (SCC) for switching said electrical power supply to said
selected light block or blocks for the execution of said selected
light function.
7. The driver device (P) according to claim 2, wherein said at
least one controller is suitable for delivering a control signal
for controlling a level of power (SCA) for the execution of said
selected light function.
8. The driver device (P) according to claim 7, wherein said control
signal for controlling said level of power (SCA) controls a pulse
width modulation of said electrical power supply adapted for the
execution of said selected light function.
9. The driver device (P) according to claim 7, wherein said control
signal for controlling said level of power (SCA) controls a level
of amplitude of said electrical power supply adapted for the
execution of said selected light function.
10. The driver device (P) according to claim 1, wherein said at
least one controller comprises a first input for a reception of
said first execution control signal (SCF_DRL) and a second input
for a reception of said second execution control signal
(SCF_TI/PL).
11. The driver device (P) according to claim 10, wherein said at
least one controller comprises a first output for the delivery of
said control signal for controlling said level of power (SCA) and
at least one second output for the delivery of said switching
control signal (SCC).
12. The driver device (P) according to claim 1, wherein said driver
device comprises a power module (PU) comprising an output (PU4),
said power module being suitable for delivering said electrical
power supply on its output as a function of said control signal for
controlling said level of power (SCA).
13. The driver device (p) according to claim 12, wherein said power
module (PU) comprises a first input (PU1) connected to said first
output of said at least one controller to receive said control
signal for controlling said level of power (SCA) delivered by said
at least one controller.
14. The driver device (P) according to claim 12, wherein said drive
device comprises a switch (SW) comprising a first input (SW1)
connected to said output (PU4) of said power module (PU) to receive
said electrical power supply, said switch being arranged to switch
said electrical power supply to said selected light block or
blocks.
15. The driver device (P) according to claim 14, wherein said
switch (SW) comprises at least one second input (SW2) connected to
said second output of said at least one controller to receive said
switching control signal (SCC) delivered by said at least one
controller.
16. A light device, notably for lighting and/or signaling, for a
motor vehicle comprising a plurality of light modules (LED_DRL/PL,
LED_TI), wherein said light device comprises a driver device (P)
for a plurality of light modules according to claim 1.
17. The light device according to claim 16, wherein said light
device comprises a first light block (LED_DRL/PL) suitable for
selectively executing a first and a second light function and a
second light block (LED_TI) suitable for executing a third light
function.
18. The light device according to claim 17, wherein said first
light function is a daytime running light, said second light
function is a position light and said third light function is a
turn indicator.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to French Application No.
1360592 filed Oct. 30, 2013, which application is incorporated
herein by reference and made a part hereof.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to a driver device for a plurality of
light blocks of a motor vehicle and a light device for a motor
vehicle incorporating such a driver device.
[0004] 2. Description of the Related Art
[0005] In the current driver devices for light blocks of a motor
vehicle, the structure of such circuits usually comprises a
controller provided with a power stage for each of the light blocks
implementing one function or at most a group of two light
functions.
[0006] The architecture of such a structure is represented in FIG.
1, relative to the prior art, for the control signals for the
daytime running light, or DRL, light function, grouped together
with the position light, PL, light function (PL standing for
Parking Light), these two functions being driven by a common driver
device controlling a common light block, denoted LED_DRL/PL, and,
for the control signal of the turn indicator TI light function (TI
standing for Turn Indicator).
[0007] Such an architecture in fact requires two driver devices,
each provided with a power stage, and three distinct inputs, the
grouping of the control of the daytime lighting DRL and position
light PL functions however requiring separate inputs for the
abovementioned control signals.
[0008] However, a recent change in the regulations concerning the
implementation of motor vehicle lighting and/or signaling devices
allows the grouping together of the control signals for the light
functions of a vehicle, when this grouping does not compromise
either the reliability or the safety of the assembly.
SUMMARY OF THE INVENTION
[0009] The object of the present invention is the implementation of
a driver device and of a light device for motor vehicles, in which
a grouping of the control signals of the light functions makes it
possible to reduce the number of inputs of the abovementioned
driver device.
[0010] Another object of the present invention is, furthermore, the
implementation of a driver device and of a light device for motor
vehicles by virtue of the architecture of which a single power unit
is implemented for all the light functions implemented.
[0011] Another object of the present invention is also the
implementation of a driver device and a light device for motor
vehicles that makes it possible to control a single light block
allowing for the execution of a plurality of light functions.
[0012] Another object of the present invention is finally the
implementation of a driver device and a light device for motor
vehicles that makes it possible to significantly simplify the
complexity and the bulk of the wiring of the light functions of the
motor vehicles and reduce the equipment costs thereof.
[0013] The object of the present invention is thus a driver device
for a plurality of light blocks of a motor vehicle, the driver
device comprising at least two inputs, each of the inputs being
suitable for receiving, respectively, a first and a second
execution control signals, the driver device being suitable for
selecting at least one of the light blocks as a function of at
least one of the execution control signals and delivering an
electrical power supply to the selected light block, the driver
device being characterized in that it comprises at least one
controller receiving the execution control signals, the controller
being suitable for delivering, as a function of the logic state of
the execution control signals, a switching control signal for
switching the electrical power supply to the selected light block
or blocks and a control signal for controlling the level of power
of the electrical power supply of the selected light block or
blocks.
[0014] In an advantageous embodiment of the invention, each
execution control signal received by the driver device also
constitutes an electrical power supply, the driver device
converting these execution signals into the electrical power supply
that has to be switched by the controller to the selected light
block or blocks.
[0015] Advantageously, the driver device is suitable for selecting
a light function to be executed as a function of a combination of
the logic states of the execution control signals received on the
inputs of the device and for selecting at least one of the light
blocks for the execution of the selected light function.
[0016] Light function should be understood to mean a part or even
all of a predetermined regulatory photometric function.
[0017] In one embodiment of the invention, the driver device is
suitable for selecting a light function out of a predetermined
number of selectable light functions, the number of inputs for
execution control signals for the device is less than the
predetermined number of selectable light functions.
[0018] If appropriate, each light block driven by the driver device
is suitable for performing a number of light functions strictly
less than the predetermined number of selectable light
functions.
[0019] Preferably, the driver device is suitable for selecting at
least two distinct light functions for one and the same
predetermined execution control signal received on one of the
execution control signal inputs of the device.
[0020] If so desired, the device can be suitable for selecting a
light function to be executed as a function of an activation table
receiving as input the logic state of each of the execution control
signals and delivering the light function to be selected.
[0021] If appropriate, the activation table is implemented by a
look-up table in the controller or by a microprogram driven by the
controller. As a variant, the activation table can be produced in
the form of a logic circuit.
[0022] For example, the first and second execution control signals
can each occupy an `ON` state or an `OFF` state.
[0023] Advantageously, the driver device selects a first light
function when the first and second execution control signals each
occupy an `ON` state.
[0024] The driver device can also select a second light function
when the first execution control signal occupies an `ON` state and
when the second execution control signal occupies an `OFF`
state.
[0025] The driver device can even select a third light function
when the first execution control signal occupies an `OFF` state and
when the second execution control signal occupies an `ON`
state.
[0026] Advantageously, the controller is suitable for delivering
the switching control signal for switching the electrical power
supply to the selected light block or blocks for the execution of
the selected light function.
[0027] If appropriate, the controller is suitable for delivering
the switching control signal in the form of a plurality of
switching control subsignals, the plurality of subsignals
comprising as many subsignals as there are light blocks that can be
driven by the driver device, each subsignal controlling the
switching of the electrical power supply of a single light block
and the switching of the electrical power supply of a light block
that is only controlled by a single subsignal. In this case, when
the driver device selects a light function, the controller delivers
a plurality of control subsignals. At least one subsignal of this
plurality controls the switching of the electrical power supply to
the light block suitable for executing the selected light function
whereas the other subsignal or subsignals prevent the switching of
the electrical power supply to the other light block or blocks.
[0028] Also advantageously, the controller is suitable for
delivering the control signal for controlling the level of power
for the execution of the selected light function.
[0029] For example, the control signal for controlling the level of
power can control a pulse width modulation of the electrical power
supply adapted for the execution of the selected light
function.
[0030] According to another example, the control signal for
controlling the level of power can also control the level of
amplitude of the electrical power supply adapted for the execution
of the selected light function.
[0031] In one embodiment of the invention, the controller comprises
a first input for the reception of the first execution control
signal, a second input for the reception of the second execution
control signal.
[0032] If necessary, the controller can comprise a first output for
the delivery of the control signal for controlling the level of
power and at least one second output for the delivery of the
switching control signal.
[0033] Advantageously, the driver device comprises a power module
comprising an output, the power module being suitable for
delivering the electrical power supply on its output as a function
of the control signal for controlling the level of power. The
electrical power supply can therefore be pulse width modulated
according to a duty cycle determined according to the control
signal for controlling the level of power and/or exhibit a level of
amplitude determined according to the control signal for
controlling the level of power so that its power is adapted to the
execution of the selected light function and in particular to the
light power needed for the execution of this light function
selected by the selected light block or blocks so as to fulfill the
regulatory requirements applicable to this light function.
[0034] If necessary, the power module comprises a first input
connected to the first output of the controller to receive the
control signal for controlling the level of power delivered by the
controller.
[0035] Preferably, the driver device comprises a switch comprising
a first input connected to the output of the power module to
receive the electrical power supply, the switch being arranged to
switch the electrical power supply to the selected light block or
blocks.
[0036] If necessary, the switch comprises at least one second input
connected to the second output of the controller to receive the
switching control signal delivered by the controller.
[0037] Another object of the invention is a light device, notably
for lighting and/or signaling, for a motor vehicle comprising a
plurality of light modules, characterized in that it comprises a
driver device for the plurality of light modules according to the
invention.
[0038] If necessary, each light block is suitable for performing a
number of light functions strictly less than the predetermined
number of light functions that can be performed by the light
device.
[0039] Advantageously, the light device comprises a first light
block suitable for selectively executing a first and a second light
functions and a second light block suitable for executing a third
light function.
[0040] Preferably, the first light function is a position light,
the second light function is a daytime running light and the third
light function is a turn indicator.
[0041] Advantageously, each light block of the plurality of light
blocks comprises at least one LED for executing the light function
or functions that can be executed by this block.
[0042] The driver device and the light device for a motor vehicle
that are the object of the invention are applicable to the
equipment of motor vehicles of any type.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
[0043] They will be better understood on reading the following
description and studying the following drawings, in which:
[0044] FIG. 1 concerns the prior art;
[0045] FIG. 2 represents, for purely illustrative purposes, the
functional block diagram of a driver device for a plurality of
light blocks of a motor vehicle according to the invention;
[0046] FIG. 3 represents, for purely illustrative purposes, a
detailed diagram of implementation of the driver device as
represented in FIG. 2; and
[0047] FIG. 4 represents, by way of illustration, an activation
table that makes it possible to implement the driver device of FIG.
2, in the context of the non-limiting example of the switching of
the daytime running lights DRL, of the turn indicator TI lights
function and of the position lights PL function of a motor
vehicle.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0048] A more detailed description of a controller of a driver
device for a plurality of light blocks of a motor vehicle according
to the invention is now given in conjunction with FIG. 2.
[0049] FIG. 2 shows a driver device P for two light blocks
LED_DRL/PL and LED_TI of a motor vehicle.
[0050] The light block LED_DRL/PL is suitable for selectively
executing a first function of position light PL type and a second
light function of daytime running light DRL type. The light block
LED_TI is suitable for executing a third light function of turn
indicator TI type.
[0051] The driver device P comprises two inputs P1 and P2. Each of
the inputs P1 and P2 is suitable for respectively receiving a first
and a second electrical power supply SCF_DRL and SCF_TI/PL. These
first and second electrical power supplies respectively constitute
first and second execution control signals SCF_DRL and SCF_TI/PL
that can each occupy an "ON" state or an "OFF" state.
[0052] The driver device P comprises at least one controller 1. The
controller 1 comprises a first input 11 for the reception of the
first execution control signal SCF_DRL and a second input 12 for
the reception of the second execution control signal SCF_TI.
[0053] The controller 1 is suitable for selecting a light function
out of the TI, PL and DRL functions to be executed as a function of
a combination of the logic states of the execution control signals
SCF_DRL and SCF_TI/PL such that the driver device P can select the
light block out of the blocks LED_DRL/PL and LED_TI so as to
deliver an electrical power supply to this selected block for the
execution of the selected light function. It is moreover noted that
the number of execution control signal inputs of the device is less
than the number of light functions that can be performed by the
light blocks LED_DRL/PL and LED_TI.
[0054] To this end, the controller 1 comprises an activation table
AT implemented in the form of a look-up activation table AT and a
microcontroller .mu.C reading this look-up activation table AT. As
a variant, the activation table AT could be implemented in the form
of a microprogram directly driven by the microcontroller .mu.C.
[0055] The activation table AT receives as input the logic state of
each of the execution control signals SCF_DRL and SCF_TI/PL and
delivers as output the light function to be executed.
[0056] The activation table AT selects:
[0057] the first light function PL when the first and second
execution control signals SCF_DRL and SCF_TI/PL each occupy an "ON"
state;
[0058] the second light function DRL when the first execution
control signal SCF_DRL occupies an "ON" state and when the second
execution control signal SCF_TI/PL occupies an "OFF" state; and
[0059] the third light function TI when the first execution control
signal SCF_DRL occupies an "OFF" state and when the second
execution control signal SCF_TI/PL occupies an "ON" state.
[0060] In this way, the activation table AT is suitable for
selecting two distinct light functions DRL or PL for one and the
same logic state of the execution control signal SCF_DRL received
on the input P1 of the driver device P.
[0061] The microcontroller .mu.C delivers, as a function of the
selected light function, a switching control signal for switching
the electrical power supply SCC to the selected light block and a
control signal for controlling the level of power of the electrical
power supply SCA for the selected light block so that said selected
light block executes the selected light function.
[0062] The controller 1 comprises a first output 14 for the
delivery of the control signal for controlling the level of power
SCA and a second output 13 for the delivery of the switching
control signal SCC.
[0063] The driver device P comprises a power module PU comprising
first, second and third inputs PU1, PU2 and PU3 and one output PU4.
The first input PU1 of the power module PU is connected to the
first output 14 of the controller 1 to receive the control signal
for controlling the level of power SCA delivered by the controller
1. The second and third inputs PU2 and PU3 respectively receive the
first and second execution control signals SCF_DRL and
SCF_TI/PL.
[0064] The power module PU converts the execution control signals
SCF_DRL and SCF_TI/PL into an electrical power supply as a function
of the control signal for controlling the level of power SCA and
delivers this power supply on its output PU4. For example, the
control signal for controlling the level of power SCA can order a
pulse width modulation of the electrical power supply and/or the
level of amplitude of the electrical power supply such that the
power of the electrical power supply is adapted for the execution
of the selected light function. Thus, the power module PU delivers,
on its output PU4, an electrical power supply that is pulse width
modulated according to a duty cycle determined according to the
control signal for controlling the level of power SCA and/or
exhibiting a level of amplitude determined according to the control
signal for controlling the level of power SCA such that its power
is adapted to the execution of the selected light function and in
particular to the light power needed for the execution of this
light function so as to fulfill the regulatory requirements
applicable to this light function.
[0065] The driver device P moreover comprises a switch SW
comprising a first input SW1 connected to the output PU4 of the
power module PU to receive the electrical power supply and a second
input connected to the second output 13 of the controller 1 to
receive the switching control signal SCC delivered by the
controller 1.
[0066] As a function of the switching control signal SCC delivered
by the controller 1, the switch SW switches the electrical power
supply to the selected light block for the execution of the
selected light function.
[0067] The functional diagram of the driver device P according to
the invention as represented in FIG. 2 can advantageously be
implemented in a nonlimiting embodiment as described in conjunction
with FIG. 3, as follows.
[0068] As represented in FIG. 3, the driver device P comprises the
above-mentioned controller 1, consisting of a microcontroller .mu.C
with which the activation table AT is associated. The controller 1
receives the execution control signals SCF_DRL and SCF_TI/PL and
comprises a 5 volt voltage regulator REG allowing for its power
supply.
[0069] The controller 1 delivers the switching control signal SCC
in the form of two switching control subsignals SCC_DRL/PL and
SCC_TI.
[0070] The switch SW comprises a first switching circuit SW1 to the
light block LED_DRL/PL and a second switching circuit SW2 to the
light block LED_TI. Each of the abovementioned switching circuits
consists of a transistor switch TS1, TS2 controlled by a control
transistor TC1, TC2, each receiving one of the switching control
subsignals SCC_DRL/PL, respectively SCC_TI. The emitter electrode
of the transistor TS1, TS2 constituting the corresponding
transistor switch is directly connected to the corresponding light
block LED_DRL/PL, respectively LED_TI. The collector electrode of
the transistor TS1, TS2 constituting the transistor switch is
itself connected to the output of the voltage regulator REG.
[0071] It will therefore be understood that the subsignal
SCC_DRL/PL controls the switching of the electrical power supply
only to the light block LED_DRL/PL whereas the subsignal SCC_TI
controls the switching of the electrical power supply only to the
light block LED_TI. In this case, when the controller 1 selects a
light function, one of the subsignals SCC_DRL/PL, SCC_TI controls
the switching of the electrical power supply to the light block
suitable for executing the selected light function whereas the
other subsignal prevents the switching of the electrical power
supply to the other light block.
[0072] Finally, the power module PU comprises a power transistor
switch TP controlled by a pulse width modulation control circuit
PWM. The collector of the power transistor TP is directly connected
to a common terminal of the corresponding light blocks LED_DRL/PL
and LED_TI and a feedback circuit from a resistor connected in the
emitter of the abovementioned power transistor TP makes it possible
to drive the pulse width modulation control circuit PWM.
[0073] The pulse width modulation control circuit PWM receives the
control signal for controlling the level of power, SCA.
[0074] It will thus be understood that the modulation power
transistor TP makes it possible, from the signal controlling the
amplitude of the abovementioned power supply signal delivered by
the controller 1, to consequently modulate, by pulses, the power
supply signal for the lighting/signaling blocks LED_DRL/PL or
LED_TI, for the execution of the selected lighting/signaling
function by the corresponding lighting/signaling block.
[0075] Finally, FIG. 4 shows, in table form, the truth table of the
logical combination of the logic states of the execution control
signals in the exemplary application of FIG. 3.
[0076] The first two columns on the left give the logic value of
the execution control signal SCF_DRL, respectively of the execution
control signal SCF_TI/PL, and the last two columns on the right,
the logic value of the switching control subsignal SCC_DRL/PL,
respectively of the switching control subsignal SCC_TI.
[0077] Thus, the logic combination rules establishing the values at
the output of the look-up table can be stated as follows:
[0078] when the execution control signal SCF_DRL is in the OFF
logic state and when the execution control signal SCF_TI/PL is in
the OFF logic state, the switching control subsignal SCC_DRL/PL is
in the OFF logic state and the switching control subsignal SCC_TI
is in the OFF state;
[0079] when the execution control signal SCF_DRL is in the OFF
logic state and when the execution control signal SCF_TI/PL is in
the ON logic state, the switching control subsignal SCC_DRL/PL is
in the OFF logic state and the switching control subsignal SCC_TI
is in the ON state;
[0080] when the execution control signal SCF_DRL is in the ON logic
state and when the execution control signal SCF_TI/PL is in the OFF
logic state, the switching control subsignal SCC_DRL/PL is in the
ON logic state and the switching control subsignal SCC_TI is in the
OFF state; and
[0081] when the execution control signal SCF_DRL is in the ON logic
state and when the execution control signal SCF_TI/PL is in the ON
logic state, the switching control subsignal SCC_DRL/PL is in the
ON logic state and the switching control subsignal SCC_TI is in the
ON state.
[0082] It will thus be understood that, on the one hand, each of
the switching control subsignals SCC_DRL/PL and SCC_TI makes it
possible to ensure the switching of the electrical power supply to
the lighting/signaling blocks LED_DRL/PL, respectively LED_TI, and
that, on the other hand, the control signal SCA, delivered jointly
and in correspondence with the abovementioned switching signal,
makes it possible to route the level of power of the power supply
for the execution of the selected light function.
[0083] While the system, apparatus, process and method herein
described constitute preferred embodiments of this invention, it is
to be understood that the invention is not limited to this precise
system, apparatus, process and method, and that changes may be made
therein without departing from the scope of the invention which is
defined in the appended claims.
* * * * *